The below mentioned article provides short notes on Williamsoniella.
Williamsoniella belongs to family Wielandiellaceae of Bennettitales. Thomas (1915) described it as a Jurassic genus. Its fossils are found in the form of compressions. The best known and most investigated species is W. coronata (Fig. 6 19).
The plant possessed a dichotomously branched stem bearing spirally arranged leaves. The leaves were oblong or lanceolate in shape, and each possessed a prominent midrib and many closely-packed lateral veins.
The flowers were terminal in position and bisexual. They possessed no floral bract at their basal portion. The microsporophyll’s or stamens were present at the base of the flower. A median ridge was present on the adaxial side of each stamen. Several pollen-containing synangia were present on both the sides of the ridge (Fig. 6.20).
The gynoecium consisted of a centrally located conical receptacle, which was broad at the base and tapered gradually. The receptacle had a capitate, naked and sterile tip. The middle part of the receptacle had many inter-seminal scales and stalked seeds.